SUM is the spreadsheet equivalent of an open invite: it welcomes everything into the total, whether it belongs there or not.

I keep running into situations in Excel where I want to calculate a conditional sum, but my criterion is something along the lines of "Include cell B1 if cell A1 is a number, likewise B2 and A2, B3 ...

Mastering Excel goes far beyond SUM and VLOOKUP. By learning functions like COUNT, AVERAGE, SUMIF, SUBTOTAL, XLOOKUP, and INDEX/MATCH, you can find opportunities to improve your Excel sheet. Some ...